Catalanoite is a rare sodium phosphate. It was approved as a distinct mineral species in 2002, from material found at Laguna de Santa María, Los Andes Department, Salta Province, Argentina.

Hardness

Mohs

Luster

Vitreous to resinous

Streak

White

Transparency

Transparent

mineralrare

Catalanoite

Catalanoite is a rare sodium phosphate. It was approved as a distinct mineral species in 2002, from material found at Laguna de Santa María, Los Andes Department, Salta Province, Argentina.

Hardness: 2
Luster: Vitreous to resinous
Streak: White
Transparency: Transparent

No image

Is this catalanoite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch catalanoite with a known reference. Catalanoite sits at Mohs 2, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: white.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous to resinous.
4
Match the color range
Compare against the expected color range: colorless.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: microscopic crystals, pyramidal, tabular.

Often confused with

Catalanoite vs. its common look-alikes, and how to tell them apart in the field.

Often found alongside catalanoite

Minerals reported to co-occur with catalanoite. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: Na₂(HPO₄)·8H₂O
Mohs hardness: 2
Density: 1.74 g/cm³
Colors: Colorless
Streak: White
Luster: Vitreous to resinous
Transparency: Transparent
Crystal system: Orthorhombic
Crystal habit: Microscopic crystals, pyramidal, tabular
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: It is an evaporite mineral formed in a desert playa lake

Where rockhounds find catalanoite

Classic worldwide localities

Laguna de Santa Maria, about 5 km east of the Argentina-Chile border, in the Andean Puna, Los Andes Department, Salta Province, Argentina (type locality)

Field-hunting tip

Where it forms: It is an evaporite mineral formed in a desert playa lake. If you start seeing gypsum, alunite in float, you are in the right ground. Typical habit: microscopic crystals, pyramidal, tabular. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify catalanoite?+

Mohs hardness is 2. Luster: vitreous to resinous. The streak is white. Common colors include colorless.

Where is catalanoite found?+

Notable localities include Laguna de Santa Maria, about 5 km east of the Argentina-Chile border, in the Andean Puna, Los Andes Department, Salta Province, Argentina (type locality).

What rocks look like catalanoite?+

Catalanoite is most often confused with Alunogen, Halotrichite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with catalanoite?+

Catalanoite commonly co-occurs with Gypsum, Alunite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does catalanoite form in?+

Where it forms: It is an evaporite mineral formed in a desert playa lake. Working float back to the host body is the standard way to chase a fresh occurrence.

What is catalanoite used for?+

Catalanoite is used in collector.

Find catalanoite on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.